Compound antibacterial mildew-proof oriented strand board and preparation method thereof

Abstract

The invention discloses a compound antibacterial and mildew-proof oriented strand board and a preparation method thereof, the antibacterial and mildew-proof oriented strand board comprises a core layer and a surface layer, and an adhesive layer of the surface layer comprises the following effective components in parts by weight: 10 parts of an adhesive and 0.001-0.0025 part of an antibacterial and mildew-proof agent. Wherein the main components of the compound antibacterial and mildew-proof agent are organic 1, 2-benzisothiazolin-3-ketone and a copper-zinc mixed system loaded montmorillonite mixture, the adhesive is an isocyanate adhesive, the antibacterial efficiency of the prepared antibacterial and mildew-proof oriented strand board can reach 99%, and the prepared compound antibacterial and mildew-proof oriented strand board is excellent in structural performance, good in anti-bacterial and mildew-proof performance and good in anti-bacterial and mildew-proof performance. The requirements of daily household life boards can be met.

Description

Technical Field

[0001] The invention relates to a method for preparing a composite antibacterial and mildew-proof oriented strand board, in particular to an antibacterial and mildew-proof oriented strand board and a preparation process thereof, and relates to the technical field of wood processing. Background Art

[0002] Oriented strand board is made of small-diameter logs, which are processed into long and narrow flakes by a flaker, sorted, dried and glued, and then oriented by a special laying head, and then hot-pressed into structural boards. It is collectively called man-made board together with plywood, particleboard and fiberboard.

[0003] The production process of oriented strand board mainly includes raw material preparation, strand drying, strand sorting, strand gluing, strand directional paving, hot pressing and other processes. The raw materials are processed by the flaking machine, and then dried in stages by the single-channel dryer. Then, the shavings and spray glue are mixed by the glue mixer, and then mechanically oriented and paved, and then enter the press for hot pressing. The hot-pressed board is cooled, trimmed, sanded, inspected and other subsequent processes.

[0004] Chinese Patent 202111478955.4 discloses a method for preparing a low-odor particleboard. The invention separates the talcum powder by adjusting the wind speed, and further adjusts the hot pressing process to remove the odor in the particleboard without affecting the performance of the board itself, thereby obtaining a low-odor particleboard. Chinese Patent 201910953750.3 discloses a waterproof and antibacterial oriented strand board and a preparation method thereof. The invention uses a hot pressing process to spray nanosilver suspension and chitosan bismuth complex suspension to spray the shavings in a mist form. The obtained board has excellent physical properties, good dimensional stability, and no formaldehyde release. The above-mentioned preparation materials have been studied for the waterproof durability and antibacterial properties of the board, but the antibacterial slow-release and mildew-proof properties of the wood have not been treated. Therefore, the invention of an oriented strand board with antibacterial slow-release and mildew-proof properties is a topic that needs to be explored urgently. Summary of the invention

[0005] The invention discloses a composite antibacterial and mildew-proof oriented strand board and a preparation method thereof, the purpose of which is to use a composite antibacterial and mildew-proof agent and an isocyanate adhesive to mix and hot-press the composite antibacterial and mildew-proof oriented strand board, the process operation is simple and easy to repeat, the product quality is good, the physical and mechanical properties are good, the nail holding force is strong, the internal stress distribution is uniform, and the dimensional stability is good.

[0006] After optimization, the key technologies for preparing antibacterial and mildew-proof oriented strand board are as follows: A method for preparing a composite antibacterial and mildew-proof oriented strand board comprises the following steps (1) Weigh 10 g of calcium montmorillonite and 100 g of ethanol aqueous solution (9:1), heat and stir at 80 °C and condense and reflux for 5 minutes; (2) Weigh 3.5 g of octadecyltrimethylammonium chloride and stir for 4 h in a water bath at 80 °C. Let stand at room temperature for 12 h, then filter using a vacuum pump; (3) The filter cake obtained in step (2) was placed in an oven at 105°C for 48 hours to dry the water, ground with a mortar, and passed through a 100-mesh sieve to obtain modified montmorillonite (MMT); (4) Weigh 1.5 g zinc chloride, heat in a 70°C water bath, and stir in a constant temperature water bath for 24 h; (5) Weigh 10 g of the pretreated montmorillonite obtained in step (3), stir at 70°C for 24 h, centrifuge, wash, dry overnight in an oven at 70°C, grind, and sieve through a 300-mesh sieve to obtain the zinc oxide-loaded montmorillonite antibacterial material (ZnO-MMT); (6) Weigh 10 g of ZnO-MMT obtained in step (5), weigh 1.8 g of copper sulfate, add 100 g of deionized water to dissolve, heat in a 70°C water bath, stir at a constant temperature for 8 h, and age at 70°C for 6 h; (7) The solution obtained in step (6) was vacuum filtered and rinsed with deionized water until copper ions were no longer detected. The solution was placed in a 70°C oven to dry overnight and ground. The solution was passed through a 300-mesh standard sieve. A copper ion and zinc oxide composite loaded montmorillonite antibacterial material was obtained. (Cu 2+ / ZnO-MMT); (8) Weigh 5-6 g of 1,2-benzisothiazolin-3-one and 2 g of Cu in step (7). 2+ / ZnO-MMT, dissolved in 100 ml of deionized water; (9) Add 0.002 g of Dow dispersant and 0.001 g of anti-settling agent to the solution obtained in step (8), and stir at room temperature for 4 h to finally obtain an antibacterial and antifungal agent; (10) A single-channel dryer is used for medium-temperature drying. The drying process is divided into three stages, including pre-drying stage, drying stage, and equalization stage. The large and small wood chips are dried to a moisture content of 2-5%.

[0007] (11) Using a wood shavings screen to sort the two-way wood shavings obtained in step (10), using a disc screen to screen the large wood shavings, using a drum screen to screen the fine wood shavings, and using a swing screen to further screen the fine wood shavings.

[0008] (12) The wood chips sorted in step (11) are divided into large and small wood chips and put into the surface and core layer wood chip silo, and the curing agent, glue and wood chips are mixed by using an atomizing nozzle, wherein the rotation speed of the atomizing nozzle is 10000r / min.

[0009] (13) The shavings obtained in step (12) are paved in a directional manner. The upper and lower surface layers are paved in a directional manner in the length direction. Wide and long shavings are paved on the surface layer. The core layer is paved in a directional manner in the transverse direction. Fine and small shavings are paved on the core layer. The height of the upper and lower slabs is detected by a paving machine, and the distance is adjusted to reduce the up and down floating of the shavings, thereby finally obtaining a slab.

[0010] (14) The slab laid in step (13) is pre-pressed and then hot-pressed. The pre-pressing temperature is 40-60°C, the preset pressure is 2.10-4.5MPa, and the pre-pressing time is 40-130s per mm thick antibacterial and mildew resistant oriented strand board. The hot-pressing temperature is 125-140°C, the hot-pressing pressure is 3-6.05MPa, and the hot-pressing time is 60-140s per mm thick antibacterial and mildew resistant oriented strand board, thereby obtaining the antibacterial and mildew resistant oriented strand board. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 (a, b) TEM images of ZnO-MMT before modification, (c, d) TEM images of ZnO-MMT after modification, (e, f) TEM images of Cu before modification 2 + TEM images of / ZnO-MMT, (g, h) modified Cu 2+ TEM image of / ZnO-MMT.

[0012] Figure 2 (a, b) TEM images of ZnO-MMT2 slurry before and after modification, (c, d) TEM images of Cu before and after modification 2+ TEM image of / ZnO-MMT slurry.

[0013] Figure 3 Infrared spectra of melamine formaldehyde resin with different proportions of nano antibacterial slurry added.

[0014] Figure 4 The diameter of the inhibition zone of melamine formaldehyde resin with different proportions of nano antibacterial slurry added.

[0015] Figure 5 Scanning electron microscope energy spectrum of boards with different antimicrobial agent addition ratios.

[0016] Figure 6 Antibacterial activity effect diagram of montmorillonite-based composite antibacterial particleboard.

[0017] Figure 7 Antibacterial activity effect diagram of melamine impregnated paper veneer.

[0018] Figure 8 SEM image of melamine impregnated paper veneer.

[0019] Fig. 9 Effect of nano-antibacterial agents on the contact angle of melamine impregnated paper veneer. DETAILED DESCRIPTION

[0020] In order to make up for the above shortcomings, the present invention provides a composite antibacterial and mildew-proof oriented strand board and a preparation method thereof to solve the problems in the above background technology. The technical solution of the present invention is further described below in combination with specific examples, but the protection scope and implementation methods of the present invention are not limited thereto.

[0021] Embodiment 1: Wood shavings drying: A single-channel dryer is used to dry large and small wood shavings to a moisture content of 2% using medium-temperature drying technology.

[0022] Wood shavings gluing: Heat the wood shavings and adhesive to 50°C and reduce the moisture content to 5%.

[0023] Slab processing: The shavings are paved in a directionally laid, with the upper and lower surface layers paved in the length direction. Wide and long shavings are laid on the surface layer, and the core layer is paved in the transverse direction. Small and broken shavings are laid on the core layer. The paving machine is used to detect the height of the upper and lower slabs, adjust the distance, reduce the up and down floating of the shavings, and finally obtain the slab.

[0024] Oriented Strand Board: Pre-pressing temperature is 50℃, pre-pressing time is 3MPa, and pre-pressing time is 80s for every mm thickness of the Oriented Strand Board. Hot pressing temperature is 130℃, hot pressing pressure is 3MPa, and hot pressing time is 90s for every mm thickness of the Oriented Strand Board to obtain the Oriented Strand Board.

[0025] Embodiment 2: A single-channel dryer is used, and medium-temperature drying is adopted. The drying process is divided into three stages, including a pre-drying stage, a drying stage, and an equilibrium stage, and the large and small wood chips are dried to a moisture content of 2-5%.

[0026] The two-way shavings coming out of the dryer are sorted by a shavings screen, the large shavings are screened by a disc screen, the fine shavings are screened by a drum screen, and the fine shavings are further screened by a swing screen.

[0027] The sorted wood chips are divided into large and small wood chips and enter the surface and core layer wood chip silo. The curing agent, glue and wood chips are mixed by an atomizing nozzle, wherein the rotation speed of the atomizing nozzle can reach 10000r / min.

[0028] The wood shavings are laid in a directionally laid manner. The upper and lower surface layers are laid in a directionally laid manner in the length direction. Wide and long wood shavings are laid on the surface layer. The core layer is laid in a transverse direction. Fine and small wood shavings are laid on the core layer. The height of the upper and lower slabs is detected by a paving machine, and the distance is adjusted to reduce the up and down floating of the wood shavings, and finally a slab is obtained.

[0029] The paved slab is pre-pressed and then hot-pressed. The pre-pressing temperature is 50°C, the pre-pressing time is 3MPa, and the pre-pressing time is 80s per mm thick antibacterial and mildew-proof oriented strand board. The hot-pressing temperature is 130°C, the hot-pressing pressure is 3-6.05MPa, and the hot-pressing time is 90s per mm thick antibacterial and mildew-proof oriented strand board, thus obtaining a composite antibacterial and mildew-proof oriented strand board.

[0030] According to the test methods specified in GB LY / T1580-2010, GB18580-2017, ISO20585, GBT17657-2013, and JC / T2039-2010, the test results of the antibacterial and mildew-proof oriented strand board of Example 2 are as follows:

[0031] Table 1 Antibacterial and antifungal effects of two embodiments of the present invention

Claims

1. A composite mildew-proof and antibacterial oriented strand board comprises a core layer and a surface layer, characterized in that It is a three-layer structure. The upper and lower surface layers are paved in a directionally paved manner in the length direction. Wide and long large shavings are paved on the surface layer. The core layer is paved in a horizontally directional manner. Fine shavings are paved on the core layer. The height of the slab is tested to reduce the free floating of shavings.

2. The compound mildew-proof and antibacterial oriented strand board as claimed in claim 1, characterized in that The effective ingredients and weight proportions of the mildew and antibacterial agent are as follows: 10 parts of adhesive and 0.001-0.0025 parts of mildew and antibacterial agent. The effective ingredients and weight proportions of mildew and antibacterial agent are 3:

1. The adhesive is isocyanate and the antibacterial agent is copper-zinc mixed system loaded montmorillonite.

3. The mildew and antibacterial agent as claimed in claim 2 is characterized in that the raw materials are pretreated by weighing 10 parts of calcium-based montmorillonite and 100 parts of ethanol aqueous solution (9:1), heating and stirring at 80°C and condensing and refluxing for 5 minutes, weighing 3-5 parts of octadecyltrimethylammonium chloride, stirring for 4 hours in a water bath at 80°C. Let it stand at room temperature for 12 hours, and then filter it with a vacuum pump. The final filter cake is placed in an oven at 105°C for 48 hours to dry the moisture, and sieved through a 100-mesh sieve using a mortar to obtain the modified montmorillonite.

4. The mildew and antibacterial agent as claimed in claim 2 is characterized in that the preparation of zinc oxide-loaded montmorillonite (ZnO-MMT) is as follows: 1-3 parts of zinc chloride are weighed, heated in a water bath at 70°C, and stirred at a constant temperature in the water bath for 24 hours. 10 parts of pretreated montmorillonite are added, and stirred at a constant temperature of 70 degrees Celsius for 24 hours. Centrifugal separation and washing are performed. The mixture is placed in an oven to dry at 70°C overnight, ground, and sieved through a 300-mesh sieve. The zinc oxide-loaded montmorillonite antibacterial material (ZnO-MMT) is obtained.

5. The mildew and antibacterial agent as claimed in claim 2 is characterized in that copper ions and zinc oxide composite supported montmorillonite (Cu 2+ / ZnO-MMT), weigh 10 parts of ZnO-MMT obtained in claim 4, weigh 1-2 parts of copper sulfate, add 100 parts of deionized water to dissolve, heat in a 70°C water bath, stir at a constant temperature for 8 hours, and age at 70°C for 6 hours. Rinse with deionized water solution, and no copper ions are detected. Place at 70°C to dry overnight and grind. Pass through a 300-mesh standard sieve. Obtain copper ion and zinc oxide composite loaded montmorillonite antibacterial material (Cu 2+ / ZnO-MMT).

6. The mildew and antibacterial agent as claimed in claim 2 is characterized in that 5-6 parts of 1,2-benzisothiazolin-3-one and 2-3 parts of Cu in claim 5 2+ / ZnO-MMT was dissolved in 100 parts of deionized water, 0.002 parts of Dow dispersant and 0.001 parts of anti-settling agent were added, and the mixture was stirred at room temperature for 4 hours to obtain a composite antifungal and antibacterial agent.

7. The method for preparing the compound mildew-proof and antibacterial adhesive according to claim 2, characterized in that: 0.001-0.0025 parts of antifungal and antibacterial agent are mixed and dispersed with 10 parts of isocyanate to prepare antifungal and antibacterial adhesive.

8. The process for preparing a composite mildew-proof and antibacterial oriented strand board according to claim 2, characterized in that The preparation of the raw material includes a core layer and a surface layer, and the raw material selected is radiata pine.

9. The process for preparing a composite mildew-proof and antibacterial oriented strand board according to claim 2, characterized in that The wood shavings are dried in stages using a single-channel dryer to reduce the moisture content to 2-5%.

10. The process for preparing a mildew-proof and antibacterial oriented strand board according to claim 2, characterized in that The hot pressing process is to pre-press the paved slab first and then perform the hot pressing process. The pre-pressing temperature is 40-60°C, the preset pressure is 2.10-4.5MPa, and the pre-pressing time is 40-130s per mm thick mildew-proof and antibacterial oriented strand board. The hot pressing temperature is 125-140°C, the hot pressing pressure is 3-6.05MPa, and the hot pressing time is 60-140s per mm thick mildew-proof and antibacterial oriented strand board, so as to obtain a composite mildew-proof and antibacterial oriented strand board.

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